Conduction System

Question 1

Stage 1: Cardiac impulse is initiated…

Answer 1

…from the SA node in the right atrium.

Question 2

Stage 2: Impulse travels…

Answer 2

…down the atrium wall causing both atria to contract.

Question 3

Stage 3: Cardiac impulse…

Answer 3

…reaches and activates the AV node in the right atrium.

Question 4

Stage 4: The impulse is passed down…

Answer 4

…the Bundle of His in the septum of the heart.

Question 5

Stage 5: Bundle of His splits…

Answer 5

…into left and right branches to spread the impulse down to the bottom of the heart.
The impulse travels up and around the walls via a network of Purkinje Fibres which causes both ventricles to contract.

Question 6

Stage 6: Ventricles relax…

Answer 6

…and the cycle repeats.